Tech - Brake Lead/Pull and Frt Brake Wear (Repl. Frt Brake Pads, Rr Brake Shoes)
| Subject: | Brake Lead/Pull and Front Brake Wear (Replace Front Brake Pads And/Or Rear Brake Shoes) |
| Models: | 1992-1999 Chevrolet and GMC C/K Cab Chassis, Crew Cab, and Pickup Models with Power Brakes (RPO JB8) |
| 1992-99 Chevrolet and GMC C/K Suburban Models with 8600# GVW (RPO C6P) |
| 1996-2000 Chevrolet and GMC G Vans with Power Brakes (RPO JD7 & JB8) and GVW's of 7,700# up to 9,500# (RPO's C3F, C6P, & E23) |
This bulletin is being revised to update information in the Models Section and Correction Information. Please discard Corporate Bulletin Number 99-05-24-001 (Section 5 -- Brakes).
Condition
Some owners may comment about the vehicle leading or pulling to either side while applying the brakes, and premature front brake wear, especially vehicles that have been used to tow a heavy load.
Cause
The condition may be caused by wearing of the front brake material. Improvements to the above conditions can be gained through brake material modifications. On the Suburban models, the best performance from this new brake material can be achieved with replacing the brake combination valve.
Correction
Replace the rear brake shoes with P/N 18029651. THIS FIX DOES NOT APPLY TO THE 13 x 2 1/2 BRAKE, DURASTOP™ P/N 18029650, OR ANY OTHER SIZE. On Suburban models, a brake combination valve must be replaced. ALL OTHER MODELS (C/K, G Van), NO BRAKE COMBINATION VALVE CHANGE IS REQUIRED. Refer to the Drum Brakes or Hydraulic Brakes subsection of the appropriate Service Manual. For G2/G3 Series Vans only (with GVW's of 7,700# up to 9,500# -- RPOs C3F, C6P, E23) also replace the front brakes pads with P/N 12471685. Refer to the Disc Brake subsection of the appropriate Service Manual.
Important: The new front brake pad material has been selected for improved wear characteristics. Some customers may experience increased brake noise from this brake pad and should be advised that some squeal is a characteristic of this particular material.
Important: If you encounter disc brakes that are extremely worn on the inboard side, with very little wear to the outboard side, verify the clearance between the caliper and the steering knuckle bracket stops.
MEASURE THE CLEARANCES INDIVIDUALLY AND ADD THE CLEARANCES TOGETHER FOR TOTAL CLEARANCE BEFORE REMOVING THE CALIPER. If the caliper (total clearance) to the steering knuckle stops is under 0.26 mm (0.010 in), correct this by filing metal off at the steering knuckle stops in order to obtain a total clearance of 0.26 to 0.60 mm (0.010 to 0.024 in). DO NOT FILE METAL OFF OF THE CALIPER. Refer to the Disc Brake subsection of the appropriate Service Manual for additional information on this procedure.Parts Information
Part Number | Description | Qty |
|---|---|---|
18029651 (17452R Canada) | Shoe Kit, RR Drum Brk (13 x 3.5 in.) | 1 |
12471685 | Pad Kit, Frt Disc Brk | 1 |
15650150 (92-94 Suburbans) | Valve Asm., Brake Comb. | 1 |
12548265 (95 and Newer Suburbans) | Valve Kit, Brake Comb. | 1 |
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
H0257 | Shoes and Linings, Drum Brake - R&R or Replace (Rear) | Use published labor operation time |
H0042 | Pads, Disc Brake - R&R or Replace (Front) | 1.0 hr* |
H0780 | Valve, Brake Combination - Replace | Use published labor operation time |
*This time is updated from the current Labor Time Guide. The next issue will contain this change. | ||
